The present invention relates to the field of overhead protective structures for excavating machines such as hydraulic excavators and shovels to protect the machine and the machine operator from falling objects such as rocks and bolders dislodged during excavation operations. It is well known to provide protective structures for the top of such machines. However, since they may be subjected to high impact compressive forces and bending moments, such structures must be mounted on the machine frame by heavy mounting members sufficient to withstand such bending moments. The required heavy mounting members increase the weight and complexity of such protective structures and interfere with vision from the operator's cab.